HOXA9 and acute myeloid leukemia: We also measured the expression levels of LIC associated genes Meis1, Hoxa9, Pbx1 and Pbx3 in Mac-1+c-Kit+ LICs from recipient mice transplanted with WT, P2x1-null, Bcat1-overexpressing WT or P2x1-null AML cells by qRT-PCR.